Bathtub



FIG. 1 is a top plan view of a bathtub showing my new design;

FIG. 2 is a rear elevational view thereof;

FIG. 3 is a perspective view taken from the front, top and one side thereof; and

FIG. 4 is an elevational view taken from the side opposite that shown in FIG. 3. 

The ornamental design for a bathtub, as shown. 